RU2025547C1 - Method for bleaching cellulose - Google Patents

Method for bleaching cellulose Download PDF

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Publication number
RU2025547C1
RU2025547C1 SU904743775A SU4743775A RU2025547C1 RU 2025547 C1 RU2025547 C1 RU 2025547C1 SU 904743775 A SU904743775 A SU 904743775A SU 4743775 A SU4743775 A SU 4743775A RU 2025547 C1 RU2025547 C1 RU 2025547C1
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RU
Russia
Prior art keywords
ozone
gas
carried out
cellulose
carrier gas
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Application number
SU904743775A
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Russian (ru)
Inventor
Хенриксон Кай
Лаксен Торольф
Пельтонен Юхани
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А.Альстрем Корпорейшн
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Application filed by А.Альстрем Корпорейшн filed Critical А.Альстрем Корпорейшн
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Publication of RU2025547C1 publication Critical patent/RU2025547C1/en

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    • D—TEXTILES; PAPER
    • D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
    • D21C—PRODUCTION OF CELLULOSE BY REMOVING NON-CELLULOSE SUBSTANCES FROM CELLULOSE-CONTAINING MATERIALS; REGENERATION OF PULPING LIQUORS; APPARATUS THEREFOR
    • D21C9/00—After-treatment of cellulose pulp, e.g. of wood pulp, or cotton linters ; Treatment of dilute or dewatered pulp or process improvement taking place after obtaining the raw cellulosic material and not provided for elsewhere
    • D21C9/10—Bleaching ; Apparatus therefor
    • D21C9/147—Bleaching ; Apparatus therefor with oxygen or its allotropic modifications
    • D—TEXTILES; PAPER
    • D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
    • D21C—PRODUCTION OF CELLULOSE BY REMOVING NON-CELLULOSE SUBSTANCES FROM CELLULOSE-CONTAINING MATERIALS; REGENERATION OF PULPING LIQUORS; APPARATUS THEREFOR
    • D21C9/00—After-treatment of cellulose pulp, e.g. of wood pulp, or cotton linters ; Treatment of dilute or dewatered pulp or process improvement taking place after obtaining the raw cellulosic material and not provided for elsewhere
    • D21C9/10—Bleaching ; Apparatus therefor
    • D21C9/147—Bleaching ; Apparatus therefor with oxygen or its allotropic modifications
    • D21C9/153—Bleaching ; Apparatus therefor with oxygen or its allotropic modifications with ozone

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  • Life Sciences & Earth Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Wood Science & Technology (AREA)
  • Paper (AREA)
  • Steroid Compounds (AREA)
  • Investigating Or Analysing Biological Materials (AREA)
  • Saccharide Compounds (AREA)

Abstract

FIELD: cellulose treatments. SUBSTANCE: method for bleaching cellulose includes treatment of cellulose mass with gaseous mixture of ozone and carrier gas to produce foamy mass containing water, cellulose fiber and mixture of ozone and carrier gas. Treatment is carried out at fiber concentration in foamy mass of 5-25%. Treatment is carried out in one or several stages, mainly, in two stages. After the first stage, the residual gas is drawn-off and the second stage is conducted with use of said residual gas in the presence of additional amount of fresh gaseous mixture of ozone and carrier gas. Carrier gas is used in form of oxygen or nitrogen. EFFECT: higher efficiency. 4 cl

Description

Изобретение относится к технологии отбелки целлюлозы с использованием озона и предназначено для изготовления высококачественных целлюлозных полуфабрикатов для бумаги и химической переработки. The invention relates to a technology for bleaching pulp using ozone and is intended for the manufacture of high-quality pulp semi-finished products for paper and chemical processing.

Известен способ отбелки целлюлозы путем обработки целлюлозной массы газообразной смесью озона и транспортирующего газа - кислорода под давлением (Tappi, 1986, 69, N 7, с.84-88). A known method of bleaching cellulose by treating the pulp with a gaseous mixture of ozone and a transporting gas - oxygen under pressure (Tappi, 1986, 69, No. 7, p. 84-88).

Однако этот способ не позволяет осуществлять процесс при средней концентрации массы - выше 3%. However, this method does not allow the process to be carried out at an average mass concentration of above 3%.

Целью изобретения является проведение процесса отбелки при более высоких концентрациях массы для его интенсификации. The aim of the invention is to conduct the bleaching process at higher concentrations of the mass for its intensification.

Для этого в способе отделки целлюлозы путем обработки целлюлозной массы газообразной смесью озона и транспортирующего газа под давлением, в процессе обработки создают пеноподобную массу, содержащую воду, целлюлозное волокно и смесь озона и транспортирующего газа, обработку проводят при концентрации целлюлозного волокна в массе 5-25%. To do this, in the method of finishing cellulose by treating the pulp with a gaseous mixture of ozone and transporting gas under pressure, a foam-like mass containing water, cellulose fiber and a mixture of ozone and transporting gas is created during processing, the treatment is carried out at a cellulose fiber concentration of 5-25% .

Обработку проводят в одну или несколько стадий, преимущественно в две. При обработке в две стадии после первой стадии остаточный газ удаляют, а вторую стадию проводят в присутствии дополнительного количества свежей газообразной смеси озона и транспортирующего газа. В качестве последнего предпочтительно использовать кислород или азот. Processing is carried out in one or several stages, mainly in two. When processing in two stages after the first stage, the residual gas is removed, and the second stage is carried out in the presence of an additional quantity of a fresh gaseous mixture of ozone and transporting gas. As the latter, it is preferable to use oxygen or nitrogen.

Газообразная смесь содержит указанные компоненты, предпочтительно в следующих количествах, мас.% озон 1-10; транспортирующий агент 90-99. The gaseous mixture contains these components, preferably in the following amounts, wt.% Ozone 1-10; transporting agent 90-99.

Остаточный газ после первой и/или второй стадий может использоваться в качестве горючего газа в котле-утилизаторе. The residual gas after the first and / or second stages can be used as combustible gas in a recovery boiler.

Смешивание газообразной смеси с целлюлозной массой может осуществляться в реакционному сосуде, например псевдоожижающем смесителе. Mixing the gaseous mixture with the pulp can be carried out in a reaction vessel, for example a fluidizing mixer.

На других стадиях отбелки в случаях многостадийных отбеливающих процессов в качестве отбеливающих реагентов могут использовать хлор, перекисные соединения, двуокись хлора, гидроксид натрия или ферменты. At other stages of bleaching in cases of multi-stage bleaching processes, chlorine, peroxide compounds, chlorine dioxide, sodium hydroxide or enzymes can be used as bleaching agents.

П р и м е р. Озон смешивают с транспортирующим газом - кислородом в суспензии целлюлозной массы при концентрации 10%. Озон расходуется в ходе отбеливания, но не расходуется транспортирующий газ. Суспензию из газа и целлюлозной массы поддерживают под давлением 7 бар с созданием пеноподобной массы. После отбеливания транспортирующий газ отделяют и утилизируют. PRI me R. Ozone is mixed with carrier gas - oxygen in a suspension of pulp at a concentration of 10%. Ozone is consumed during bleaching, but carrier gas is not consumed. The gas and pulp suspension is maintained at a pressure of 7 bar to create a foam-like mass. After bleaching, the carrier gas is separated and disposed of.

Процесс ведут при следующих значениях основных параметров: концентрация волокна в пеноподобной массе 12%, давление 6 бар, расход озона 60 кг, целлюлозная масса + вода 8 м3 на тонну целлюлозной массы, введенный газ 75 м3/т (концентрация озона 10%), газ, нерастворенный во всей воде 75 м3/т.The process is carried out at the following values of the main parameters: fiber concentration in the foam-like mass of 12%, pressure 6 bar, ozone consumption of 60 kg, pulp + water 8 m 3 per ton of pulp, introduced gas 75 m 3 / t (ozone concentration of 10%) , gas undissolved in all water 75 m 3 / t.

В настоящее время без использования настоящего изобретения технически невозможно обеспечить устойчивую пену с помощью 8 м3 целлюлозы + воды и 75 м3 газа. Это достигается двумя путями: дальнейшее увеличение давления до 12 бар и уменьшение объема газа до 33 м3; многократная дозировка озонсодержащего газа с промежуточным удалением транспортирующего газа. Например, тройная дозировка снижает объем газа до 11 м3 при соотношении к 8 м3 воды + волокно, что технически неосуществимо.Currently, without using the present invention, it is technically impossible to provide a stable foam with 8 m 3 of cellulose + water and 75 m 3 of gas. This is achieved in two ways: a further increase in pressure to 12 bar and a decrease in gas volume to 33 m 3 ; multiple dosage of ozone-containing gas with intermediate removal of the carrier gas. For example, a triple dosage reduces the volume of gas to 11 m 3 with a ratio of 8 m 3 of water + fiber, which is technically not feasible.

В предлагаемом способе при отбелке озоном происходит смешение транспортирующего газа с суспензией целлюлозной массы с образованием пены, при этом происходит реакция, после реакции имеет место удаление транспортирующего газа и дальнейшее уменьшение объема газа, когда это необходимо, благодаря созданию давления и многостадийной дозировке. In the proposed method, when bleaching with ozone, the carrier gas is mixed with a suspension of pulp to form a foam, a reaction occurs, after the reaction, the carrier gas is removed and the gas volume further decreases, when necessary, due to the creation of pressure and a multi-stage dosage.

Таким образом, предлагаемый способ обеспечивает интенсификацию процесса отбелки целлюлозы. Thus, the proposed method provides an intensification of the process of bleaching pulp.

Claims (4)

1. СПОСОБ ОТБЕЛКИ ЦЕЛЛЮЛОЗЫ путем обработки целлюлозной массы газообразной смесью озона и транспортирующего газа под давлением, отличающийся тем, что в процессе обработки создают пеноподобную массу, содержащую воду, целлюлозное волокно и смесь озона и транспортирующего газа, и обработку проводят при концентрации целлюлозного волокна в массе 5 - 25%. 1. METHOD FOR BELLING CELLULOSE by treating the pulp with a gaseous mixture of ozone and carrier gas under pressure, characterized in that during the treatment process a foam-like mass containing water, cellulose fiber and a mixture of ozone and carrier gas is created, and the treatment is carried out at a concentration of cellulose fiber in the pulp 5 - 25%. 2. Способ по п.1, отличающийся тем, что обработку проводят в одну или более стадий. 2. The method according to claim 1, characterized in that the treatment is carried out in one or more stages. 3. Способ по пп.1 и 2, отличающийся тем, что обработку проводят по меньшей мере в две стадии, причем остаточный газ удаляют между каждой предыдущей и последующей стадией обработки и все стадии обработки проводят в присутствии дополнительного количества свежей газообразной смеси озона и транспортирующего газа. 3. The method according to claims 1 and 2, characterized in that the treatment is carried out in at least two stages, the residual gas being removed between each previous and subsequent processing stage, and all processing stages are carried out in the presence of an additional amount of a fresh gaseous mixture of ozone and transporting gas . 4. Способ по п.1, отличающийся тем, что в качестве транспортирующего газа используют кислород или азот. 4. The method according to claim 1, characterized in that oxygen or nitrogen is used as the transporting gas.
SU904743775A 1989-05-10 1990-03-22 Method for bleaching cellulose RU2025547C1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
FI892243A FI89516B (en) 1989-05-10 1989-05-10 Foerfarande Foer blekning av cellulosamassa med Otson
FI892243 1989-05-10

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RU2025547C1 true RU2025547C1 (en) 1994-12-30

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SU904743775A RU2025547C1 (en) 1989-05-10 1990-03-22 Method for bleaching cellulose

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Country Link
US (3) US5266160A (en)
EP (2) EP0397308B1 (en)
JP (2) JPH0340888A (en)
AT (1) ATE111371T1 (en)
CA (2) CA2012771C (en)
DE (2) DE69028797T2 (en)
FI (1) FI89516B (en)
RU (1) RU2025547C1 (en)
WO (1) WO1990013344A1 (en)

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US6579411B1 (en) 2003-06-17
EP0479789A1 (en) 1992-04-15
FI892243A0 (en) 1989-05-10
EP0397308A3 (en) 1991-04-17
CA2012771C (en) 1996-03-26
ATE111371T1 (en) 1994-09-15
FI89516B (en) 1993-06-30
DE69028797T2 (en) 1997-03-06
US6547923B1 (en) 2003-04-15
WO1990013344A1 (en) 1990-11-15
FI892243A (en) 1990-11-11
DE69028797D1 (en) 1996-11-14
EP0397308B1 (en) 1996-10-09
JPH05500241A (en) 1993-01-21
EP0479789B1 (en) 1994-09-14
CA2012771A1 (en) 1990-11-10
EP0397308A2 (en) 1990-11-14
DE69012563D1 (en) 1994-10-20
CA2054727A1 (en) 1990-11-11
JPH0340888A (en) 1991-02-21
US5266160A (en) 1993-11-30

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